Quoted from Fester1984:Got the motor mounted they twitch and move round ever so slightlay but not how they should
You may have the shaft of the motor touching the sides of hole it goes through. I just had this same problem on mine. I added a couple washers to one side to make it centered in the hole better and now it rotates great.
Someone replaced the motor on mine though and it is not the right one, the shaft is too short. I also can tell they either made new washers or cut down ones that were there already and it didn't help.